Perpetual motion, Leonardo da Vinci

by RichMac, published

Perpetual motion, Leonardo da Vinci by RichMac Jan 24, 2013

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A model made from one of da Vinci's drawings. This is an elegant and simple version of the 'overbalanced wheel', which supposedly has more weight on one side and will spin forever.
A fun model to make, with an interesting history.


Designed for 8 mm balls, but 5-10mm will work.

Perpetual motion doesn't seem to work, what am I doing wrong?

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It just occurred to me; there is already a working perpetual motion machine... It's called the ocean.

Runs off the gravity from the moon. sorry.
And not perpetual, the moon is moving away from the earth at 1"/yr (and accelerating) and will eventually fly off into space, leaving the oceans flat and motionless.

Maybe if you put a bearing in the center it can move more time.

I find it interesting how many people claim perpetual motion is impossible, how do you know? we will all die long before a "perpetual motion" machine that is running can be proven to be running "forever"...how do you know that it did not stop right after the last human dies? Many "Laws" and "Theories" have been disproved and replaced..."Laws" and "Theories" are always expected to be firm until proven otherwise. That is the Scientific Method...

because it violates the laws of thermodynamics.

well perpetual motion would be possible in an orbit but these should be called perpetual energy machines

I highly doubt that any of the laws of physics have been debunked...theories? Sure, but no laws -- or at least none that I could find. Perpetual motion is only possible in a hypothetical "ideal world". It would require exactly 100% of its energy to be sustained in the system (whatever machine or whatnot); any more than 100% and it would violate the law of conservation of mass; any less and it would be perpetual, duh.

law of conservation of energy*

aha right, but they're interchangeable naturally

Nah, just so closely related that it gets this easy to mix them up. You're ok though, have a great 3d print filled life!

So - we can tell it is interchangeable :-)

one more thing, an Atom is a perpetual motion machine, just a machine too small to derive useful work from other than a bomb.

Do explain the atom. Things change at the scale of subatomic particles. The properties of quatum mechanics become more noticable.

Yes, things change at the quantum level, but you still exists, because the atom still exists and still "runs". what's your point?

What do you mean by "runs"? There is no motion (at least in the conventional sense) at the subatomic level. The nucleus of am atom is made of 'particles' made from fluctuations in a field. I mean I guess you could say that the inherent vibrations of structures are perpetual. But eventually even that motion is not everlasting.

"There is no motion (at least in the conventional sense) at the subatomic level. The nucleus of am atom is made of 'particles' made from fluctuations in a field" Then there are the Electrons.

Even cooled to almost 0 Kelvin, there is still movement due to quantum fluctuations.
can you prove that motion is not everlasting?

Moving the goalposts does not enable you to win the debate.

lol... I didnt notice this comment: my bad.

Electrons dont travel; they just pop in and out of existence. So temperature doesnt matter in this convention of motion.

"duh"...well said...you must be edumacated. You completely missed the point, the only way to prove perpetual motion is to redefine it. "It would require exactly 100% of its energy to be sustained in the system (whatever machine or whatnot); any more than 100% and it would violate the law of conservation of mass; any less and it would be perpetual." So, feel free to tell all those scientists that found evidence that changed theories , they cannot do that. Btw, a "Theory" is is based on Facts. i sincerely hope you are not a Flat Earther.

Redefine perpetual motion? Do explain. Laws are very different than theories. Theories can be changed because they explain the 'why' of a phenomenon. Laws cannot be changed.

You are one of those people that continually redirects and asks slanted questions until the other person gets tired of explaining it to you, then you claim victory in your own little mind, because you have no reasonable rebuttal.
I'm done explaining to you, you are wasting my time and energy.

Incredible...I wasn't the one to bring up subatomic mechanics; check for yourself. As for your touting, you are the kind of person that makes me feel smart.

sorry, i should have been more specific, i meant redefine the proof requirements.
currently we have defined a Perpetual Machine as a machine that will run forever.
Since no one lives forever and the human race is not guaranteed to live forever, there is no way to validate that.
Time is not a useful measurement for validation of a Perpetual Machine. We are making new discoveries all the time,
Many scientific “laws” were proven wrong throughout the history of humankind.
the best example would be the earth revolves around the sun.
when it comes to science, it’s best to keep an open mind.

I agree with your notion that perpetual motion cannot be completely confirmed with a definite ampunt of time. However, I have yet to find a law that has been proven to be false. And the revolution of the earth around the sun is also not indefinite.

The only Perpetual Motion is the never-ending search for it!

Does anybody know it efficiency?

This model is awesome!

I showed it to the mayor of my town, and we decided to run the whole place on these things. There's just a field in some guy's backyard where they all sit. Don't touch them, though. Highly electrocuted. In fact, we built a whole battery factory in this guy's backyard. (BTW his name is N. Ergizer) One last thing - we have an iPhone charging service - "Send us ur phone, we'll charge it!"

Don't work it's dommage

Put it in a vacuum and make the center axel hover in a magnetic levitating frictionless bearing. Isaac Newton's law of conservation of energy states that energy cannot be created or destroyed, only transferred. So if you remove the two places where energy is transferred out of the wheel, namely friction and air resistance, then with a push to start it, the wheel should spin forever. At least until the sun dies and the earth shrivels up.

magnetic perpetual motion attempts are the most plausable

Except that all magnets will eventually loose there magnetism.

Do you have any ideas or designs about this? I want to try something.

The only issue is that magnets can become demagnetized

how long would that take?

Depends on the type of magnet.

I didn't think you would actually respond.

A permanent magnet, if kept and used in optimum working conditions, will keep its magnetism for years and years. For example, it is estimated that a neodymium magnet loses approximately 5% of its magnetism every 100 years. Optimum working conditions include; not subjecting the magnet to temperatures above its maximum operating temperature, protecting from corrosion and not subjecting them to strong demagnetising fields.

Great design.

For all those people getting upset because it doesn't actually function you need to research da Vinci's projects. 99% were concepts and theories on paper. They look cool and there is a lot of history behind each one but most of them don't have any practical application.

Some did work and you can buy them as plastic model kits. I would like to see them re-created as 3D printable projects ;)

Must i have a motor to turn it?

Must i have a motor to turn it?

Stupidest thing I have ever printed. Printed for my kid for tomorrow school event and the stupid thing wouldn't even do a single turn. Perpetual motion? This is a worst spinning wheel I have ever seen out of all normal shaped and not balanced wheels. What are the balls doing there? Well, they keep the wheel from turning, turns better without them, at least rotates for 15 seconds without balls... Total waste of time. Should of read the description before printing this useless piece of plastic.

I love this, you unintentional discovered for yourself exactly why over balance wheels don't work. You're absolutely right, about it spinning better without the balls. They seem like they would crate motion, but really they steal energy away from the rotation. I'm sorry it didn't work out like you planned, but your observation was great.

That's what you get for waiting until the last minute to do something. If you planned ahead and experimented, you wouldn't have had this experience.

Hahah did you truly think it would work? it seemed like you where mad that it wasn't perpetual motion lol.

Zennis are you stupid or plain blind?? I repeated myself 3 times for stupids like you already. And yet dumb asses keep posting that I thought perpetual motion would work. I am not as stupid as some commenter here, so for especially dumb I will repeat fourth time - no i didnt think, you dumb ass, read attentively or don't read at all.

i wouldn't go calling people a dumbass when you can barely type a coherent sentence lmao

Pucking at my third language? How many do you speak except your one? Lol. I can express myself fairly well. Another dumb ass?

I speak two languages, but thats beside the point. The real focus here is the fact that you are mentally impaired and I honestly feel bad for your son to have such a shitty, rude, and dumb father.

Anything else? Lol. Why don't you get a life and start living it instead of texting to people like me online?

Guys just chill. It didn't work for me either

You don't understand the hobby, do you?

Things don't always print right the first time. Everyone prints with different settings and has different printers. I printed this and it spins for 45-55 seconds with the balls. It's not in the RepRap/3D printing spirit to degrade someone's creation, especially when it's YOUR fault it didn't come out right. There is no excuse for your behavior. It wouldn't be acceptable even if the entire print was a spaghetti failure.

Check yourself.

It printed absolutely perfectly, except for the concept that simply doesn't work. I am not the type of sucker to complain about my own print failures. The only reason I shared my opinion here is that someone else doesn't print it expecting it to work somewhat at least. Author posted a great copy of da vinci wheel, totally appreciated. My comments have nothing to do with 3D model author, but rather with da vinci wheel to be a stupid thing that makes zero sense, not in terms of perpetual motion, but in every other sense. And I do understand the hobby, maybe you don't. Again, my prints never fail, I know what I am doing always. This print was not an exception. If you are not OK with hearing others honest opinions, then you are at the wrong place, not me. I am sorry I am not as fake as you are, when the part works, I share that, when it doesn't - I share that. That simple.

dude, perpetual motion doesn't exist, otherwise there will be free energy for everyone. this is just a proof of concept

Comments deleted.

It is funny that you thought this would actually work.
I would be great if it did. We would no longer need to pay for electricity but sadly, perpetual motion is not possible.

dude, did you read my reply at all? You really believe someone can be that stupid to believe in perpetual motion. I said this thing does not rotate at all. Absolutely hollow wheel will rotate 100 times better. This wheel is perpetual stop, not perpetual motion. And yes, I did expect at least some small efficiency gain over normal wheel.

Yes read it and yes there are lots of people out there that believe Perpetual Motion is possible. Have a look on youtube and type in perpetual motion. Lots of comments indicate they believe it's possible. You need to chill and not take everything as a personal attack. Live, Love and enjoy life. We are only here for a short while so make the best of it.

Well, if there are lots of grown ups that do believe in perpetual motion, we've got a serious basic education problems on this planet. More shocking is the fact, that for this community that was possible to believe that I don't understand perpetual motion, more possible than actually reading my message as it is, and understanding what I actually meant, without guessing some really crazy sh%t.

Haha. Don't complain to me, I just copied it from Leonardo!
Do you really expect perpetual motion to work? This is just a lovely bit of history, apparently the unbalanced wheel goes back to the 12th century. It didn't work then! If you could read Italian, I think Da Vinci is explaining why it wouldn't work.
Enjoy the model, then explain to your kids where the fallacy is.

No, you didn't get me. Of course I expected it not to work as perpetual motion. But boy this thing is pathetic. I couldn't get it to rotate a single turn. Yes I expected it to rotate "better" than the reqular wheel at least. Not blaming anyone, just upset. Wasted time.

Sounds like your printer is printing more of an oval than a circle. your axis's aren't perpendicular. other people claim to have much more success than you, sounds like you need to learn how to tune your printer

I print drones on this printer, and they fly OK. Does it sound any OVAL to you? I design the too. This wheel printed perfectly as it should have. I was just shocked with the stupidity of the community, and the fact that it is acceptable for them, that a mature person can be so uneducated really, to not understand school facts about perpetual motion. And that they are not able to read and understand properly, and it really did bother me to explain same thing to multiple people over and over, how stupid is that?

you are just an asshole

why did you delete your first comment? cause it made you look stupid?

Great model! I've got 15 of these hooked up and charging my iPhone

I got you beat. I have 1000 running my house right now. Damn it's noisy :O)

I know that perpectual motion is impossible coz friction and energy-dissipating.
But this doesn't even turn but just swing!
Is there video of this?

Suggestion, if your going to proint this: print the wheel flat. You get a cleaner and shorter print.
True perpetual motion is impossible. BUT you should be able to simulate it. Custom base with a small hidden magnet under the decending side of the wheel. As long as the magnet pulls, the wheel should turn. Not true perpetual motion but a nice imitation of it.

Would like to see this. Not sure if it actually works...

What do you use for the "axle"?

Perpetual motion is indeed impossible. However since nearly the beginning of time electrons have been whizzing around nuclei and they haven't slowed down - how is that possible? Do they not know about the first and second laws of thermodynamics? :-)

surely if they are indeed "whizzing". electrons have orbitals not "orbits" like planets. they're probabilistic so not exactly moving like you think they are. Change in position sure, but an actual movement from one position to another in some orbit or linear motion, no not exactly.

Course you can have something perpetual as long as nothing dissipates the energy like friction, magnetic or gravitational drag. you could watch something move forever but you couldn't use any of it's motion without stopping it. our solar system's been moving around for a bit... nothing is forever but still moving without an external source of energy. Every time we do a gravity assist in space we take a minuscule amount away from an object :) you can theoretically put that back too though.

perpetual motion is somthing thats impossible

you lot must of printed it wrong because mines been spinning for weeks.It turns out that free power really is possible.
i might have to redesign it to have a bearing in it because the squeaking is driving me mad but how can i stop it to ever fit the bearing.?.

soon as you take something away from that "turning" it's stops so it ain't free power unless it produces MORE energy than it's using to spin... since it's subject to friction it will stop anyway. perhaps it will be forever spinning in space though.

It seems that if you lubricate the axis, it will spin a lot of faster than before.

does it work for you? mine didnt spin

While the first and second laws are based on mathematical arguments and many confirming observations, they are still only models and subject to revision when / if conflicting observations are made -- like all "laws" in science.
However, with regard to this particular device, conservation of momentum and energy holds, first and second law are not violated, and this wheel will always stop unless kinetic energy is added.

The thermodynamic Laws aren't observational at all, but are entirely mathematical. Free energy requires one of two conditions: Negative volume or negative mass.

The Overbalanced Wheel is a great optical illusion though.

A perpetual motion machine is a hypothetical machine that can do work indefinitely without an energy source. This kind of machine is impossible, as it would violate the first or second law of thermodynamics. So don't expect it to do anything.

It could use the gravity and centrifugal as an energy source.

Gravity is not an energy source.
"Centrifugal" is most definitely not an energy source

You can convert your potential energy (due to gravity) into kinetic energy (for example, jumping off a table) and you can convert your kinetic energy to potential energy (self explanatory). What you cannot do is create more energy.

A perpetual motion machine repeatedly converts kinetic energy to potential energy and vice versa thus causing an object to continuously and indefinitely move along a certain path. In THEORY this is possible.

In practice, every time you make the conversion you lose some energy due to real-world effects (friction, drag, etc.) so eventually your object will stop moving.

Hope this helps.

Well if it doesn't run forever, At least it will run a few days.

Comments deleted.

Yes i can also confirm it :) . I have not tought about that both sides are affected by gravity so the wheel is getting in to balance.
I dont want to create energy, i know i can not make something from nothing, i just wanted to use more energy sources.

I'm no physicist or mathematics expert, but is not the atomic structure of the plastic itself in perpetual motion? I'm referring to the electrons orbiting the nucleus. Those little machines seem to run forever!

yes, you just cannot get useful work out of them other than matter.

Hey RichMac, is this copyrighted? I would like to use and distribute it.

as something of a 2D to a 3D k tien not change enn see nad the invention each other https://www.youtube.com/watch?v=xDF0cugCoMM ;)

Soon to be leaving thingiverse because of Makerbot's behavior towards open source.
Details: http://www.fabbaloo.com/blog/2014/5/25/has-makerbot-crossed-the-line-for-some-yeshttp://www.fabbaloo.com/blog/2...

10 each 10mm balls for $9.00 + shipping, (about $10.68 total), from The Bearing Ball Store, on Amazon.
As I built mine, I wondered what Leonardo could have accomplished, if he'd had an UP! Mini, like I do!
(At least he would have proved to himself that it can't really work)!

Da Vinci figured he could 'game' the system, the leverage of the balls on the right would be enough to lift the others on the left, with some left over. He was wrong; turns out gravity is a conservative vector field, which allows it to be mathematically proven that you simply can't make an arrangement that generates power continuously from gravity. So, since that was worked out, nobody needs to waste hours and hours looking for an arrangement that works, since we know due to the intrinsic nature of gravity that there just isn't one (yay math!). Doesn't stop hundreds of people on youtube trying to do this with magnets though :-( .
So, it's a bit of history, build it as an amusement, but don't expect it to turn by itself for very long. If you actually want it to spin a long time, the best way is to use a really good bearing in the middle and glue the balls to the outer end of each track (thus you have an ordinary, boring, flywheel). The motion of the balls along the track doesn't actually help, and in fact uses up a fair bit of energy - especially when the balls on the right lose all of their kinetic energy when colliding with the outer end of the track.


I believe that if you have an exact same wheel, you place it next the other one in oppesite direction. Make the balls go from one wheel to the other when they are on a low point.

What would that accomplish? You still have to move the balls back up. You must input some energy from somewhere that is outside the system (wheel device) if you want it to keep running.

What I think dude is saying is have the ends of where the balls roll off be nothing- have them simply roll off the end of one wheel and fall onto the other, thus the ball landing suddenly will cause the wheel it landed on to budge just enough for the ball above it to roll off that wheel and fall onto the first wheel, causing that wheel to budge just enough for the next ball to roll off and fall onto the other wheel, and so on. I don't know what it would look like, but I can picture it almost like an infinity symbol, where the balls just keep falling from different sides, landing on alternating wheels with just enough force to make the wheel budge. In theory, I think this might work.

The fundamental laws of physics do not prohibit perpetual motion. But properties of physical objects conspire to prevent it.

got some 5mm balls laying around gona make this asap

Yes, but this requires 8 of them.

It can't work because the friction gets larger as the force gets more powerful on the axle, which makes the friction counter the extra force.

OK - I'll pay $300.00 US to anyone who can model this for me... http://www.youtube.com/watch?v=FLek_3Hpwushttp://www.youtube.com/watch?v... I've tried for hours in sketchup, but Im a novice at best. If interested, please message me.

Check my collection.
I have added the wheel, arm and load.

Just made it.

Alright Deal. I could do that. And I would add your name to it.
You would need some Neodymium magnets in order to make that.

So Do I have your confirmation..?

i made this was wondering were to get the medal bearings? also what kind of pin did u use?

The bearing balls can be bought from any industrial bearing shop. Or on ebay.
I made the centre bearing holes so they could be drilled out. But I just used a pin used for sewing.

can u link the bearings?

Lisa, in this house we obey the laws of thermodynamics!

The reason it doesn't work is it is almost balanced. I realize the principle is the balls roll to the outside edge to increase leverage, but with the balls closer to the center there is always MORE balls trying to be lifted. If you draw an imaginary line vertically through the center, you will see more on the left.

What about the v-gate magnetic wheel? http://youtu.be/FLek_3Hpwushttp://youtu.be/FLek_3Hpwus - Id kill to see if this actually works...

I wonder if some sort of magnetic bearing http://en.wikipedia.org/wiki/Magnetic_bearinghttp://en.wikipedia.org/wiki/M... could be used to get rid of the primary friction point?

The shape of your holes are wrong. There is a youtube video somewhere that shows one that works (even if it is only for a few minutes)

A video of it working? Find it! We want to make one!
My model is pretty close to da Vinci's, He was clever even if his helicopter never flew. He also proposed wheels with hinged arms, and shaped water or mercury channels, variations of the same concept.

Not saying that it would help much but wouldn't it be better to have an odd number of arms instead of an even number?

If you experience perpetual motion for more than 4 hours, please consult your doctor.

Just make the balls out of unobtanium and use frictionless bearings. :) or better yet have hidden air jet blowing on the wheel. Maybe some electronic whiz could. Set up an oscillating magnetic field to drive it.

In that case, just put a magnet in the center and a coil of wire around a cylinder containing the machine. Then run an electric current through the coil. :)

perpetual motion is like saying your creating something out of nothing, all the same it looks like a good object to be placed on a work desk and can spin when you get bored at work, great toy

But you can create something out of nothing, But you normally have to create a negative something at the same time. so then you are left with a positive and a negative object.

Think you missed the end of that physics lecture where they tell you that the positron and electron are formed from energy (as an example). All equations balance out eventually.

The reason that it is not working at all is this: you have 2 points of friction in the model, the centre Axel and the ball bearings rolling. The first has a LOT of friction so it is using up all of the energy almost instantly. If you fix that with a ball bearing (as suggested below) then that would dramatically increase the spin time.

But do remember, IT WILL NEVER BE ABLE TO SPIN FOREVER! As many people have mentioned perpetual motion is impossible. This is because, sadly, no matter how hard we try, friction will always exist. :), (however in computer simulations, it doesn't)

I think you'd get to the point pretty quickly where the ball bearings are using up far more energy than the axle bearing. At which point, improving the axle bearing won't make much difference. Bear in mind, each time a ball bearing collides with the end of the track, all its kinetic energy is lost.

I love how most of the comments are about how perpetual motion is impossible.

Perpetual motion demonstration: feed a 2 year old a piece of sugar candy. :)

or redbull and vodka (I do that to lost children before returning them)

Lol I'd like to see the math for that one please.

Clarke's Three Laws

  1. When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

  2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible.

  3. Any sufficiently advanced technology is indistinguishable from magic.

1: Did you use phi as a ratio in the design? #2: Magnetic balls with two magnets at the bottom on either side of the wheel... to y'know, boost it till the magnets wear out? #3: Coral Castle in Florida. Code144.

Because perpetual motion machines tend to work much better when you use phi as a ration in the design?

The universe seems to work well with phi as a ratio in the "design"... just a thought.

His has 12 balls, yours only has 8. Could that be it? I would use a bearing in the middle though!

It obviously doesn't work because you printed it in white. I believe safety cone orange or bright green are required for perpetual motion...

I'd go for red. The red makes it go faster and thus have more kinetic energy.

Red would make it spin so fast it might be dangerous. I'm thinking a nice slate grey would get it to go the right speed.

If you take enough acid, it'll look green and orange, and it'll probably spin forever, too.

hhahahaha \0/

did you try it with slighter heavier bearings? if i am not wrong, the perpetual motion is possible if the center of gravity of the entire combination of the wheel and the bearings is always closer to the circumference and to one side. Perhaps a math simulation for actually tracing the movement of the center of gravity is called for :D

There are countless complex computer simulations and calculations proving that it does work. Unfortunately my ball bearings don't understand the theory!

Citation needed. vector field theory says "it doesn't, end of discussion". Also, basic economics says it doesn't or I would have one in my basement making power.

A video of it not working would also be cool.

Next: the mechanism in peppers office in ironman 2

Would love to see a video...do you have one of it working?

Sorry, no video of it working, because is doesn't! Despite all the enthusiasm for hundreds of years, the overbalanced wheel is a delightful myth. As you turn the wheel, the extra friction of the balls slows it down quicker.

Either way, it would be cool if you posted a video showing your printed model spinning. Cool design!

You aren't doing anything wrong. Your only problem is that perpetual motion is impossible because it violates the laws of thermodynamics.

No it doesn't. Go into outer space and spin a ball. It will spin forever assuming it doesn't interact any planets, asteroids, etc. What is impossible is getting any energy out of it and having it still spin. As long as no energy is taken away from the object (aka no friction) it can in fact spin forever. But no, this isn't possible on earth unless you artificially create a vacuum and some kind of magnetic levitation so there is absolutely no friction.

That's true, but rather tangential to the issue. What you are correctly saying is that a flywheel in space can spin forever, and if you could suspend a flywheel on earth in a vacuum on frictionless bearings, it would spin forever. All true. But if you then replaced it with a wheel like this which had ball bearings sliding around and banging into the sides, it wouldn't be even close to spinning forever, even if on a frictionless bearing in a vacuum. The balls actually consume energy.

Yeah you're right, but this device obviously could never work perpetually. My point was simply that "perpetual motion" is possible.

No, he's just using the wrong kind of filament. He needs Monster Cables' ultra-gold.

A ball bearing in the center would increase the spin time dramatically I'm sure. The sleeve bearing has a ton of friction.

The balls sliding around probably use up a lot more energy than the bearing at the middle, which may be hard to accept since Da Vinci thought they would supply energy...

not to mention air resistance, might need to keep it in a vacuum too

If you put it in a vacuum, the forces of the vacuum will pull the balls off the tracks and if you try to add rail, the rails will create hundreds of times more friction that the air.

He said a vacuum, as in no air. There's still gravity.

Friction and forces in a vacuum?

Need a little engine in the middle. :)

It might be interesting to put a low friction bearing in the center...

nice but can't work, the enrgy needed to lift the ball from the low place to the up one is the same than the enrgy you can get from the up place to the low one <; the sum is zero so it can turn

if it can there would be no energy shortage anywhere

it would be interesting to glue the balls in place on one wheel, and let them roll on another wheel, and with the same force applied, see the difference in decceleration times. could be an interesting math problem to prove/disprove inertia math.

Interesting - how long have you managed to get it to spin for?

Not long at all. If you turn it slowly it stops immediately, if you turn it fast the balls fly out!

They mustn't have had friction in the 14th century ....

Friction was a 15th century invention.